【作者】 陆跃；

【导师】 陈建定；

【作者基本信息】 华东理工大学 ， 材料科学与工程， 2012， 博士

【摘要】 聚氨酯是一种以氨基甲酸酯为特征官能团的高分子聚合物,因其优异的性能而具有广泛的应用。传统聚氨酯基于其合成的原料和结构特征,在使用过程中存在诸多问题。本文采用五元环碳酸酯类单体,研究了非异氰酸酯聚氨酯(NIPU)的合成动力学、线性和体型非异氰酸酯聚氨酯的结构与性质的关系；并通过对传统聚氨酯的接枝改性,改善聚氨酯的热稳定性。本研究的新颖点主要包括以下三方面：(1)以聚乙二醇单甲醚(mPEG, Mn=2000g/mol)、丁二酸酐和碳酸甘油酯为原料,合成了一种末端为五元环碳酸酯的聚乙二醇单甲醚功能化大单体(mPEG-GC)。并以此单体为碳酸酯模型化合物,通过与正庚胺、环己胺以及2-氨基庚烷在不同温度下的反应,确立了该模型化合物的动力学参数；并研究了mPEG-GC与正庚胺反应体系转化率随反应物配比、反应物浓度、反应时间、催化剂种类及用量的关系。结果表明：五元环碳酸酯与胺的反应符合动力学二级反应,其中与正庚胺的反应活化能最低(Ea=5.63KJ/mol)。碳酸酯的转化率随反应温度和时间的增加而增大,随反应物浓度的增大先增加后减小。(2)以聚乙二醇(PEG, Mn=2000g/mol)、聚碳酸酯二元醇(PCL, Mn=2000g/mol)、丁二酸酐和碳酸甘油酯为原料,分别合成了末端为五元环碳酸酯的二官能度的聚乙二醇功能化大单体(PEG-2GC)和二官能度的聚己内酯功能化大单体(PCL-2GC)。并以这两种大分子碳酸酯单体与1,6-己二胺、4,4’-亚甲基双(环己胺)和4,4’-亚甲基二苯胺进行加成缩聚,研究了缩聚单体种类、反应条件对线性非异氰酸酯聚氨酯结构及分子量的影响；通过小分子二官能度环氧单体与二氧化碳的成环加成反应,制备了一系列双官能度的小分子类五元环碳酸酯单体。并以此类单体与聚醚胺进行加成缩聚,研究了单体结构、反应条件对聚醚型非异氰酸酯聚氨酯结构的影响；通过硅烷偶联剂,制备了一系列NIPU/SiO2交联聚合物,研究了交联密度、交联方式对聚合物结构、热力学性质及结晶形态的影响。结果表明：当反应温度为70℃、反应物浓度为1/3mol/L、反应时间为24h时,所制备的线性非异氰酸酯具有较高的分子量(Mn=25647g/mol, Mw=56482g/mol);热力学研究表明,由于非异氰酸酯中具有β羟基,能与氨基甲酸酯形成分子内氢键作用,其热稳定性优于传统的聚氨酯,但交联NIPU的热稳定性随着交联密度的增大而降低。(3)利用碳酸酯与胺基反应生成p羟基的特点,制备了含功能性单体的"click diols",并以此二元醇为单体,通过一步法原位缩聚反应,直接向传统聚氨酯主链引入了功能性单体,研究了功能性单体种类、用量对聚氨酯热稳定性、热力学性能、机械性能及表面形貌的影响；结果表明：通过侧链功能化改性,改性聚氨酯在180℃老化30min后,仍然具有较好的力学性能；热力学分析表明,聚氨酯的起始降解温度提高至330℃,降解活化能提高至386.1KJ/mol。更多还原

【Abstract】 Polyurethane polymers with ureathane functional groups and outstanding properties were widly used in many domains. But they still have many problems in the application process due to raw materials used for the synthesis of polyurethane and the feature structures of polyurethane. Monomers with five-membered cyclic carbonate were prepared in this study and the kinetics, relationships between structures and properties of non isocyanate polyurethane (NIPU) had been investigated based on the reaction of carbonate monomers with amines. The graft modification of polyurethane to improve the thermal stability was also investigated. The novel study had been divided into the following parts:(1) Functionalized poly(ethylene glycol) methyl ether (mPEG) end capped with five-membered cyclic carbonate (mPEG-GC) was synthesized from mPEG (Mn=2000g/mol), succinic anhydride and glycerol-1,2-carbonate. Reaction rate constants and activation energy were evaluated from the model reaction between mPEG-GC with amines at different conditions. The reaction conditions were optimized. The reactions between five-membered cyclic carbonate with amines obeyed a second-order reaction kinetics model. The lowest activation energy was obtained when reacted with heptylamine (Ea=5.63KJ/mol). The conversion of five-membered cyclic carbonate increased with increasing of reaction time, temperature and concentration while decreased with further increase of the concentration.(2) Functionalized poly(caprolactone) diol (PCL) and poly(ethylene glycol) (PEG) end capped with five-membered cyclic carbonate (PCL-2GC and PEG-2GC) were synthesized from PCL (Mn=2000g/mol), PEG (Mn=2000g/mol), succinic anhydride and glycerol-1,2-carbonate. Small molecualr carbonate monomers were prepared by cycloaddition of CO2 to difunctional epoxids compounds. The molecular weight, structure and properties of linear NIPU polymers were studied through polycondensation of carbonates with 1,6-hexanediamine,4,4’-methylenedianiline,4,4’-methylenebis(aminocyclohexane) and Huntsman Elastamines(?). The relationships between thermal mechanical properties, phase structure and crosslink density of crosslinked NIPU/SiO2 polymers were investigated using silane coupling agents. The enhanced thermal stability of NIPUs was benefit from the pendant hydroxyl groups which could form a stable ring structure through hydroxyl bonding to the urethane groups. The number of hydroxyl groups and thermal stability of NIPUs decreased as the crosslink density increased. The highest molecular weight of NIPU (Mn=25647g/mol, Mw=56482g/mol) was obtained under 70℃for 24h when the reactants concentration was 1/3mol/L. TG analysis showed that the thermal stability of NIPU was higher than traditional PU due to intramolecular hydrogen bonds between hydroxyl and urethane groups. The thermal stability of crosslinked NIPUs decreased as the crosslinking density increased.(3) Two series of "click diols" bearing functional groups were easily synthesized based on the derivation ofβhydroxyl during the reaction of carbonate with amine. Therefore the graft modification of polyurethanes were obtained through one-pot in-situ polycondensation of isocyanate, polyol and "click diols". The thermal stability of modified polyurethanes was improved with out any loss of mechanical properties. The initial degradation temperature and thermal degradation activation energy of the graft-modified PUs improved up to 330℃and 386.1KJ/mol respectively and the mechanical properties kept well after degraded at 180℃for 30min.更多还原